Atomic Force Microscopy of Protein Shells: Virus Capsids and Beyond

Abstract

In Atomic Force Microscopy (AFM) the probe is a nanometric tip located at the end of a microcantilever which palpates the specimen under study as a blind person uses a white cane. In this way AFM allows obtaining nanometric resolution images of individual protein shells, such as viruses, in liquid milieu. Beyond imaging, AFM also enables the manipulation of single protein cages, and the characterization a variety physicochemical properties able of inducing any measurable mechanical perturbation to the microcantilever that holds the tip. In this chapter we start revising some recipes for adsorbing protein shells on surfaces. Then we describe several AFM approaches to study individual protein cages, ranging from imaging to spectroscopic methodologies devoted to extracting physical information, such as mechanical and electrostatic properties.

Membrane-Containing Icosahedral Bacteriophage PRD1: The Dawn of Viral Lineages

“…This combination of materials and architectures provide specific mechanical properties fulfilling the requirement for protection. Singlemolecule techniques such as atomic force microscopy (AFM) have been proven to be very useful in unravelling the mechanical properties of viruses (Martin-Gonzalez et al, 2018). This information is pivotal not only to grasp their biology but also for manipulating and using them as nano-carriers of foreign cargos.…”